His great-grandson, John Lowther, was created a baronet, of Lowther in the County of Westmorland, in the Baronetage of Nova Scotia in circa 1638. He was succeeded by his grandson, the second Baronet (the son of John Lowther, eldest son of the first Baronet). He was an influential politician and held several ministerial posts during the reign of William III. In 1696 he was raised to the Peerage of England as Baron Lowther and Viscount Lonsdale. His eldest son, the second Viscount, died unmarried at an early age and was succeeded by his younger brother, the third Viscount. He was also a prominent politician. On his death in 1751 the barony and viscountcy became extinct.

The late Viscount was succeeded in the baronetcy by his second cousin, James Lowther, the fifth Baronet. He was the son of Robert Lowther, son of Richard Lowther, second son of the first Baronet. Lowther was a Member of Parliament for over twenty years and served as Lord-Lieutenant of Westmorland and Cumberland. He inherited not only the Lowther estates in Westmorland, but also the Whitehaven estates that had recently belonged to Sir James Lowther. In 1784 he was raised to the Peerage of Great Britain as Baron Lowther, of Lowther in the County of Westmorland, Baron of the Barony of Kendal in the County of Westmorland and Baron of the Barony of Burgh in the County of Cumberland, Viscount Lonsdale, Viscount Lowther and Earl of Lonsdale, with normal remainder to the heirs male of his body.[2] The Earl was childless and all his titles were heading for extinction. In 1797 he was therefore created Baron Lowther, of Whitehaven in the County of Cumberland, and Viscount Lowther, of Whitehaven in the County of Cumberland, with remainder to the heirs male of his deceased third cousin, Reverend Sir William Lowther, 1st Baronet, of Little Preston,[3] to whom he also devised his considerable estates. These titles were also in the Peerage of Great Britain. On Lord Lonsdale's death in 1802, the baronetcy and the peerages of 1784 became extinct.

He was succeeded in the barony and viscountcy of 1797 according to the special remainder by his third cousin once removed, Sir William Lowther, 2nd Baronet, of Little Preston. He was the elder son of the aforementioned Reverend Sir William Lowther, 1st Baronet, of Little Preston, great-grandson of Sir William Lowther, brother of Sir John Lowther, 1st Baronet, of Lowther (see Lowther Baronets for a more comprehensive history of this branch of the family).

In 1807 the earldom of Lonsdale was revived when he was created Earl of Lonsdale, in the County of Westmorland, in the Peerage of the United Kingdom.[4] The same year he was also made a Knight of the Garter. He was succeeded by his eldest son, the second Earl. He was a prominent Tory politician and notably served as Postmaster General and Lord President of the Council. In 1841 he was summoned to the House of Lords through a writ of acceleration in his father's junior title of Baron Lowther. He was childless and on his death the titles passed to his nephew, the third Earl. He was the eldest son of the Hon. Henry Lowther, second son of the first Earl. He represented Cumberland West in the House of Commons and served as Lord-Lieutenant of Westmorland and Cumberland. His eldest son, the fourth Earl, died without male issue at an early age and was succeeded by his younger brother, the fifth Earl. He became known as "England's greatest sporting gentleman". He was succeeded by his younger brother, the sixth Earl. As at 2010 the titles are held by the latter's grandson, the eighth Earl, who succeeded his father in 2006.

The family seat was formerly Lowther Castle in Cumbria. However, the seventh Earl lived at nearby Askham Hall and the present Earl lives at Thrimby a few miles south-east of the castle. The traditional burial place of the Earls of Lonsdale is the Lowther Mausoleum in the Churchyard of St Michael, Lowther, Cumbria.[5]

The heir presumptive is the present holder's half-brother, the Hon. William James Lowther (born 1957)
The heir presumptive's heir presumptive is his half-brother, the Hon. James Nicholas Lowther (born 1964)
The heir presumptive's heir presumptive's heir is his son James William Lancelot Lowther (born 2000)